Acid concentration measurement

Abstract

The acid concentration of a test material is measured by passing a stream of water through a mixing device at a predetermined rate, adding a predetermined volume of the test material to the water upstream of the mixing device, and measuring the electrical conductivity of the mixed effluent stream from the mixing device.

What is claimed is: 
     
       1. The method of measuring the concentration of hydrofluoric acid in a test material which contains hydrofluoric acid, acid-soluble oils and light paraffins, which method comprises passing through a mixing device at a predetermined rate a first stream of water containing a water-miscible solvent capable of dissolving the hydrocarbons present in the test material, introducing a predetermined volume of said test material into said first stream upstream from said mixing device, and measuring the electrical conductivity of the resulting mixed effluent stream from said mixing device. 
     
     
       2. The method of claim 1 wherein the amount of said test material added to said first stream is such that said hydrofluoric acid is present in said effluent stream in a concentration range wherein the electrical conductivity of said effluent stream is substantially a linear function of the acid concentration therein. 
     
     
       3. The method of claim 1 wherein said solvent is tetrahydrofuran. 
     
     
       4. The method of claim 3 wherein said first stream comprises approximately 50 percent water and 50 percent tetrahydrofuran. 
     
     
       5. The method of claim 1 wherein said solvent is isopropyl alcohol. 
     
     
       6. The method of claim 5 wherein said first stream comprises approximately 50 percent water and 50 percent isopropyl alcohol.